Suspension device for equalizing the strain on elevator cables



Nov. 9 E926. l

J. E. EVANS SUSPENSION DEvicE FOR EQUALIZING THE STRAIN oN ELEVATOR CABLES Filed Nov. 17, 192'4 2 Sheets-Shag?, 1

J. E. EVANS SUSPENSION DEVICE Fo'R EQUALIZING THE STRAIN oN ELEVATOR CABLES Filed Nv. 17, 1924 2- Sheets-Shea?l 2 L Aammgmw'..

Patented Nov. 9, 1926.

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UNITED STATES JOSEPH E. EVANS, BEDFORD, INDIANA, ASSIGNOR 0F ONE-FOURTH T0 CHARLES S.

PATENT oFF'ic.

KNIGHT, OF CHICAGO, ILLINOIS. y

SUSPENSION DEVICE FOB'EQUALIZING THE STRAIN ON ELEVATOR CABLES.

Application led November 17,1924. Serial No. 750,337.: i

My invention relates tol a device for A equalizing the strain upon the different cables of a group of cables used for hoisting and lowering 'an elevator car such as those used in transferring passengers and freight from one floor of a building to' another, especially a tall building where the lift is of considerable distance. In such cases the travel of the various cables, which all run over a common drum or hoisting pulley,

usually differs slightly, owing to slight differences in the formation of the cableV grooves, variations in stretch of the cables and othercauses. In my Patent No. 1,429,- 070, I have described an equalizing device invented by me and designed to produce -an equalization of the load of the car on the different cables, in which the elevator cables are connected to opposite ends of a group of horizontal supporting bars which spread the ends of the cables upon opposite sides of the plane of the periphery of the supporting pulley. In some installations it has been found that the necessary length ofthe equalizer bars and spread ofthe cable are such as to result in interference with stationary parts ofthe elevator framework, and one of the objects of my present invention is to produce an qualizing device which will enable the equalizer bars to be made shorter, and thus avoid the objection inA question. Other and incidental objects and advantagesv relate to asuitable and desirable arrangement and construction of the'members and parts of the device to attain the object first mentioned, all of which will be apparent from the description of my novel suspension device hereinafter given in detail, the essential elements of my invention being set forth in the appended claims. y

In the drawings accompanying this specification, Figure l is a view of my device applied to an -elevator installation of.

typical form; Fig. 2 is a side view of the device on a larger scale than Fig. l; Fig. 3 is a view at right angles .to the position of the parts in Fig. 2; Fig. 4 is atp plan view of the device; Fig.v 5 is a horizontal section, immediately above the bottomplate of the device, showing the bottom plate in plan view; and Fig. 6 is a fragmentary side view illustrating a modified form of oscillatorymember connected to a pair of the hoisting cables.

The same reference characters indicate the same parts in all .the figures of the drawlng.

Inthe ordinary and usual arrangement ofv elevatorV car" being secured to their outer ends.

My novel suspension device,'designated as a whole by the reference letter D, comprises generally frame members secured to thecar, a set of pulleys pivoted in the framework, a second set of pulleys connected to said iirst mentioned pulleys by an equalizing cable, a series of links axially connected to said second-mentioned pulleys and a set of equalizer bars (orr equivalent oscillatory l members) pivoted to said links and also connected at their opposite ends to the suspension cables. Describing these elements in detail, the frame members include a bot-tom plate V1 which may be a malleable casting, formed with downwardly extending bearing iianges 2 oriced to receive the pivotpins 3 iipon which the pulleys 4 (two in number in the present instance) are mounted toro-' The plate 1 is oriiiced to receive the tate. clamping bolts 5 whichat their top engage a composite top .frame member consisting of two pairs of end bars having opposite outwardly-extending horizontal bottom por'- tions 6 and vertical upwardly-extending top portions (la, and a pair of side plates 7 the bars and plates being firmly secured together by rivets 8, or by other suitable;

means to form a rigid structure which is ar.

ranged on top of two beams 9 9 forming a lpart ofthe frame work of the elevator car,-

number, are pivot-ally connected in pairs, the members of which are marked A and A', to the opposite ends of three pairs of equalizer bars each pair acting in unison and functioning asa single bar. In the present instance the pivotal connection includes orificed pivot blocks'` 11 formed with trunnions 12 engaging pivotv bearings in the corresponding ends-of each pair; ot' equalizer bars 10. The cables are secured by means of sockets 13 to threaded bolts 14 which pass loosely through the orifices in the trunnions and' which are each equipped with a pair of bearing nuts 15 engaging the un'der sides of the pivot blocks and serving to sustain the load on the particular cable.

Each pair of equalizer bars is pivotally connected with a link which in the present instance is of composite construction and consists of two members 16--16a which function together as one.' As will be seen by` reference to Fig. 3 of the drawing the lower link members 16--16 I have provided a cable guard 19 which serves also as a stop member. This guard consists of a central orificed block portion riveted between the link members, and connected arcuate side portions having opposite flanges arranged to overhang the pulleys 17. In case of breakage of the equalizer cable lthese guard and stop members would bring up against the side plate 7 7- of the upper portion of -the frame of the device, and sustain the weight of the car.

ForV the purpose of spacing and guiding the links in any variation of their position longitudinally I have provided erosspins 20 extending between the diii'erent sets of link members and secured to the side vplates 7-7 of thetop vframe member.

The equalizer bars 10, as will be seen by reference to the drawings are set u on the link. sections 16--16b1 atfa slight ang e with respect to radial planes of the suspension pulley, so that the lends of the'suspension cables are disposed in staggered arrangement and track approximately tangentially into the grooves of the suspension cables.

The lower pulleys 4, it will also be noted, are of such size and arranged at such .angle tothe pulleys 17 that the equalizer cable .tracks tangentially between the grooves of the dierent pulleys.

While I have found'the equalizer "bars above described a desirable and satisfactory means of pivotally connecting the cables to the equalizing pulleys, I may use, as an equivalent and also a desirable form-of oscillatory members, pulleys pivoted to the links by which the equalizer pulleys are connected, l have shown such an arrangement in Fig. 6,

the pair of cables A-A associated with theV connectlng pulley 21 being connected to forma loop engaging such pulley.

I claim:

1. A suspension device for connecting a car to a plurality of cables comprising a set of oscillatory members connected to spread pairs ot cables, links pivoted at their'upper ends' to said oscillatory members, pulleys pivoted to the lower ends lof said links, pulleys pivoted to the car, and an equallzerz cable anchored at its ends to the car and engaging said first mentionedand second vmentioned pulleys in alternation.

2. A suspension device for connecting a car to a plurality of cables comprising a set of equalizer bars connected at their opposite ends to spread pairs of cables, links pivoted at their upper ends to said bars, pulleys pivoted to the lower ends of said links, pulleys pivoted to the car, and an equalizer cable anchored at its ends to the car-and engaging saidiirst mentioned and Second mentioned pulleys in alternation. a

3. In a device of the character described having a pair of equalizer bars'connected at their ends to a pair of suspension cables and having an equalizer pulley connected to the car, a connecting link pivoted between said bars at its upper-end and forked at its lower vend to straddle said pulley and form opposite pivotal supports therefor. v

4. A suspension device according to claim 1 in which said links and the framework of the device are provided with stop elements arranged to cooperate at an extended position in excess of the normal operative position of the link.

l5. A suspension device according to claim 1 in which one or all, of said linksis equipped with a 'cable guard overhanging its associated pulley, and-the frame wprk `of said device is formed with a stop member arv ranged to cooperate with said cable guard atan extended position in excess of the nor-v inal operative position of the link.

' 6. A device of the character described hava pair ofside plates'forming'guides for the links. l

' JOSEPH E.' E vANs.

ing qa set yof oscillatory members connected -4 

